What term describes the rapid evolution of various species from a common ancestor?

The term that describes the rapid evolution of various species from a common ancestor is adaptive radiation. This process occurs when a single ancestral species diversifies into multiple forms that can exploit different ecological niches. An example of adaptive radiation can be seen in the diversification of Darwin's finches on the Galápagos Islands, where different species evolved distinct beak shapes and sizes to adapt to various food sources available in their environment.

In adaptive radiation, the presence of a variety of habitats and selective pressures often drives the evolution of new traits and behaviors, leading to a high degree of speciation over a relatively short timescale. This concept highlights how organisms can quickly adapt to changing environments or new opportunities, showcasing the dynamic nature of evolution and the interplay between organisms and their surroundings.